primary cat delete vs primary cat delete + tune

[Fen335i]

So, what's the general consensus on how much a "tune" helps with performance when you delete your primary cats. From what I understand, the biggest bang for the buck hp/tq wise, is deleting your primary cats. However, that will undoubtedly result in a CEL. The only way to get rid of that annoying light is to get a tune (or the CEL eliminator that Akra makes). So, does the "tune" really help much horsepower wise?

For example, I could buy the Turner Test pipes (or just cut out the primary cats myself and weld in some pipe, which essentially does the same thing that Turner does for $350). . . from what I understand this will yield somewhere in the neighborhood of 15-20hp. If I ADD a tune onto that mod, how much more hp/tq will I gain???? Am I looking at another 10-15hp?....so a total of 25-35hp?

I'm just a little skeptical on how much a tune will help...for the price (most tunes are around a $1,000), I'm trying to understand if the tune is really worth it...or if I could live with the CEL. I'll fail emissions regardless of the CEL being there or not by removing my primary cats.

[Dave07997S]

Originally Posted by Fen335i

So, what's the general consensus on how much a "tune" helps with performance when you delete your primary cats. From what I understand, the biggest bang for the buck hp/tq wise, is deleting your primary cats. However, that will undoubtedly result in a CEL. The only way to get rid of that annoying light is to get a tune (or the CEL eliminator that Akra makes). So, does the "tune" really help much horsepower wise?

For example, I could buy the Turner Test pipes (or just cut out the primary cats myself and weld in some pipe, which essentially does the same thing that Turner does for $350). . . from what I understand this will yield somewhere in the neighborhood of 15-20hp. If I ADD a tune onto that mod, how much more hp/tq will I gain???? Am I looking at another 10-15hp?....so a total of 25-35hp?

I'm just a little skeptical on how much a tune will help...for the price (most tunes are around a $1,000), I'm trying to understand if the tune is really worth it...or if I could live with the CEL. I'll fail emissions regardless of the CEL being there or not by removing my primary cats.

The concensus is normally the primary cat delete and software is in the 25-35rwhp range. Some have gotten a little more, some a little less but you will be in that range.

Dave

[Mahmood07]

Originally Posted by Fen335i

So, what's the general consensus on how much a "tune" helps with performance when you delete your primary cats. From what I understand, the biggest bang for the buck hp/tq wise, is deleting your primary cats. However, that will undoubtedly result in a CEL. The only way to get rid of that annoying light is to get a tune (or the CEL eliminator that Akra makes). So, does the "tune" really help much horsepower wise?

For example, I could buy the Turner Test pipes (or just cut out the primary cats myself and weld in some pipe, which essentially does the same thing that Turner does for $350). . . from what I understand this will yield somewhere in the neighborhood of 15-20hp. If I ADD a tune onto that mod, how much more hp/tq will I gain???? Am I looking at another 10-15hp?....so a total of 25-35hp?

I'm just a little skeptical on how much a tune will help...for the price (most tunes are around a $1,000), I'm trying to understand if the tune is really worth it...or if I could live with the CEL. I'll fail emissions regardless of the CEL being there or not by removing my primary cats.

Why would you fail emissions test if your CEL was removed by a tune? Do they visually check the underside of the car?

[saeedg48]

so does the car go into limp mode if the sensor isn't plugged in?

[Fen335i]

Originally Posted by Mahmood07

Why would you fail emissions test if your CEL was removed by a tune? Do they visually check the underside of the car?

I believe you will fail 02 readiness check....even with the tune that removes the CEL.

Some with HFC's are passing (barely), by driving around and warming up the car first before bringing it in..but a full on "delete" of the primaries is going to be tough to pass emissions.

[Singletrack]

Originally Posted by Mahmood07

Why would you fail emissions test if your CEL was removed by a tune? Do they visually check the underside of the car?

Car won't pass the OBD readiness with the CEL disabled for the catalyst inefficiency. In most, all?, states the shop is also supposed to do a visual inspection as well.

[Singletrack]

Originally Posted by saeedg48

so does the car go into limp mode if the sensor isn't plugged in?

Which sensor? The primary is monitored and used to make adjustments, so that would be extremely bad to disconnect. I can't see any advantage to disconnecting the secondary either as the ECU is trying to compare the signal from the primary to the secondary, so that will definitely screw it up.

[Singletrack]

Originally Posted by Fen335i

Some with HFC's are passing (barely), by driving around and warming up the car first before bringing it in..but a full on "delete" of the primaries is going to be tough to pass emissions.

My car has gone about 3k miles of mixed driving without a CEL on the fabspeed HFC with the extenders. Pretty pleased about that actually.

[L4ces]

A modular bolt in system where the cats can be easily replaced would be nice. A quick swap done the garage for emissions and then back to the primary bypasss :-). Oh well, just haring a thought.

[M3DCTBT]

A correct tune will pass readiness with the cel removed.

[Mahmood07]

Originally Posted by M3DCTBT

A correct tune will pass readiness with the cel removed.

Thanks brendan. Did you get my PM on yuppie btw?